With fast development of display technology, touch panels have been widely used in human life. At present, touch panels can be divided, in terms of structure, into Add-on mode touch panel, On-Cell touch panel and In-Cell touch panel. The Add-on mode touch panel is formed by manufacturing a touch panel and a liquid crystal display (LCD) screen separately and bonding them together to be a liquid crystal display screen with a touch function, so the Add-on mode touch panel has disadvantages of higher cost, lower light transmission rate, thicker modules, etc. The In-Cell touch panel is formed by embedding touch electrodes of a touch panel inside a liquid crystal display screen, so in the in-cell touch panel, the thickness of module can be reduced and the production cost of the touch panel can also be largely reduced, and thus the in-cell touch panel is a favorite choice for various panel manufactories.
At present, an existing capacitive in-cell touch panel is implemented by adding additional touch scanning lines and touch sensing lines directly on an existing thin film transistor (TFT) array substrate, that is, two layers of Indium Tin Oxide (ITO) strip electrodes are manufactured on the surface of the TFT array substrate which are in two different planes, wherein the Indium Tin Oxide strip electrodes on one layer cross those on the other layer. The two layers of indium tin oxide strip electrodes are used as the touch driving lines and the touch sensing lines respectively, and an induction capacitor is formed on each point at which the two layers of ITO strip electrodes intersect in different planes. An operational process of the capacitive in-cell touch panel includes detecting a voltage signal coupled across the induction capacitor through a touch sensing line when a touch driving signal is applied on an ITO strip electrode as the touch driving line; during such a process, when a human body touches the touch panel, an electrical filed of the human body will affect the induction capacitor, such that the capacitance of the capacitor will change and in turn the voltage signal coupled through the touch sensing line will change, so the position of a touch point can be determined according to variation of the voltage signal.
In the structure of the above capacitive in-cell touch panel, a new film layer is added on the existing TFT array substrate, such that the structure of the resultant TFT array substrate is relative complicated, since a new process is incorporated in the manufacture of the TFT array substrate, the production cost increases. In addition, in the structure of the above capacitive in-cell touch panel, two driving chips (IC) are simultaneously adopted for implementing touch driving and display driving respectively, so the production cost is also higher.